Stay-bolt structure.



J. R. FLANNERY.

STAY BOLT STRUCTURE.

APPLICATION FILED Nov. 21, 1916.

1,276,746. Patented Aug. 27, 1918.

WQTNESSES UNITED STATES PATENT 'QFI ICE.

JOHN ROGERS FLANNERY, OF PITTSBURGH, PENNSYLVANIA, ASSIGN-OR TO'FLANNERYBOLT COMPANY, OF

PITTSBURGH, PENNSYLVANIA.

STAY-BOLT STRUCTURE.

To all whom it may concern:

Be it known that I, JoHN Roenns FLAN- nnnv, a citizen of the UnitedStates, and a resident of Pittsburgh, in the county of Allegheny andState of Pennsylvania, have invented certain new and useful Improvements in Stay-Bolt- Structures; and I do hereby declare the following tobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to improvements in stay bolt structures forboilers, the object of the invention being to provide simple andefficient means for detecting the condition of the bolts withoutnecessity of removing said bolts from the boiler.

lVit-h this object in view, the invention consists in certain novelfeatures of construction and combinations of parts as hereinafterdescribed and pointed out in the claims.

In the accompanying drawings, Figure 1 is a sectional view of a staybolt showing an embodiment of my invention, and Fig. 2 is a separateview of the detector.

In the embodiment of my invention shown in the drawing, 1 represents astay bolt of the flexible type, the same having a spherical head 2 to beseated in a suitable bearing applied to the outer boiler sheet, as iswell known in flexible stay bolt construction. In the drawing, I haveshown the inner boiler sheet 3 through which the inner ends of the boltis threaded,the inner end of the bolt being shown as being upset asindicated at l. While I have shown this type of stay bolt to exemplifymy improvements, it will be understood that my invention is applicableto other type of stay bolts.

The stay bolt is provided with a bore, cavity or tell-tale hole 5 which,in the bolt shown in the drawing, may extend from its inner end to apoint in proximity to its head 2, and in this hole or cavity, I insert asolid material, capable of being readily removed, and which is sensitiveto the action of water, so that the contact of water therewith willcause a change in the appearance of the material.

In the embodiment of my invention shown Specificationcf Lettersitatent.Patented Aug. 27, 1918. Application filed November 21, 1916. I

Serial No. 132,609.

in the drawing, the material thus introduced into the hole in the boltconsists of a metal rod 6 having a threaded head or enlargement 7 at oneend, which head may be screwed into a recess 8 which forms a slightlyenlarged portion of the bore or hole in the bolt at the inner endthereof,said head or enlargement 7 thus serving as a closure for thehole or bore in the bolt and also serving as means for the reception ofa tool whereby the rod or detector may be removed. The rod or detector 6may be made, for example, of a metal which will oxidize, corrode orbecome discolored by the action of water, such for instance, as ferrousmetal, as iron or steel.

In the event of rupture or breakage of the bolt so that water would bepermitted to enter the bore, cavity or tell-tale hole, contact of suchwater with the metal rod will cause the latter to become oxidized,corroded or discolored and thus indicate that the bolt is defective.

From the above, it will be apparent that in inspecting the bolts, theinspector may quickly ascertain the condition of the bolt by removingthe metal detector and examining it. If he finds it to be normal inappearance, he will know that the boltis good, but if he finds saiddetector to be oxidized, corroded or discolored, he will know at oncethat the bolt is defective.

Having fully described my invention, what I claim as new and desire tosecure by Letters-Patent, is

1. A staybolt having a cavity readily accessible from one end of thebolt and closed at its other end within the bolt, and a re movabledetector located in and readily removable bodily from the accessible endof said bore, said detector being made of material which is sensitive tothe action of water to denote' the condition of the bolt.

2. A stay bolt having a bore closed at one end and open at the otherend, and a metal rod removably disposed in said bore and removablethrough said open end thereof, said metal rod being such as shall besensitive to the action of water to denote the condition of the bolt.

3. A stay bolt having a bore having one end closed Within the bolt andopen at the other end, said open end of the bore being In. testimonywhereof, I have Signed this pl'm'lded Wlth a ihreaded port-1011, and arespeclficntion m the resenee 0f two submomble (leteetol' WhlCh 1sSBHSltlVE to the scl'lblng Wrtnesses:

action of Water to denote the condition of V JUHN RQGERS FLANNERY. C:the bolt, Within said bore said detector hav- Witnesses:

ing a, threaded part at one end to enter the if ETHAN I. Donne,

threacled part of the bore OI" the bolt. Wu. G. MGNABB.

re cents eaeh, by adrll'essing; the fiommissienel' Yaimts,

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